A/C Upgrade Project starts tomorrow!
 

Well, there are just too many options to choose from when faced with repairing, replacing or upgrading the A/C on our cars. I've gone back and forth in my plans to convert to 134a, install an underbelly condenser and whether or not to go with the ProCooler. Here is my final plan - somewhat of a "best of the best" approach. Installation starts tomorrow.

Griffiths Duehl Kuehl rear fender condenser kit (impressive build quality)
Kuehl Serpentine Evaporator
All new barrier hose
Factory rebuilt Nippondenso Compressor
RennAire Desert Duty front condenser
ProCooler
Convert to 134a (since Kuehl system was designed specifically to run 134a).
Keeping my OEM tube & fin rear deck condenser w/3 cooling fans (replaced summer 06)


ProCooler arrived today. Can't wait to get started!

Mark:

what state is your AC system in now? Hold off on the Pro Cooler. I mean buy it for sure, but install it last. 134a is cheap.

Also, buy a vacuum pump if you are going to do the work yourself. The Seiko compressor is supposedly better than the ND one. I have the ND one because it was all that I could find at the time and I had been waiting on a hand built rotary compressor for months and finally said screw it.

In terms of current state of my system, I am running R12 and orig non-barrier hoses. I developed a leak in the orig evaporator as evidenced by traces of oil in the drain puddle last summer. My static pressure was 50 this AM before having the refridgerant recovered. I think this would be considered low as normal static pressure should be closer to 80-90. Additionally, on Monday it was 70 degrees ambient here and I was getting 70 degree vent temps:(

I'll be ripping the entire system out tomorrow (except for the rear condenser that I will flush) and installing the components listed above plus a high/low pressure switch.

I plan on having the system professionally charged, but I might see if the local Autozone has a vacuum pump for rent so I can check for leaks and get a good overnight pull to dry it out. My sense is the shops generally don't pull a vacuum as long or as many times as they should to get all the moisture out of the system.

awesome, pics would be appreciated.

Very similar to the path I took a couple years ago. You won't be disappointed.

The best way to ck for leaks is to use pressure, not vacuum.
If it leaks some soapy water will find it.
Nitrogen gas would be my first choice.

A few pics of the new components.

http://forums.pelicanparts.com/uploa...1204953592.jpg

Fender Condensers w/ 8" and 13" spal fans.

http://forums.pelicanparts.com/uploa...1204953677.jpg

Denso factory rebuilt compressor

http://forums.pelicanparts.com/uploa...1204953851.jpg

http://forums.pelicanparts.com/uploa...1204953918.jpg

RennAire Desert Duty front condenser is 1" thicker than OEM unit (2- 1/4" vs 1- 1/4")

http://forums.pelicanparts.com/uploa...1204954121.jpg

I see a ProCooler there so I'll mention something for the record.

It is shipped with a "FACTORY VACUUM". This is so the internal desiccant in the drier does not absorb water from the ambient air and can then absorb water from your A/C system later! Water will cause your expansion valve to freeze among other things.

You will hear that vacuum suck when you open the drier fitting caps (not the jacket caps).

Thus you should NOT OPEN or install that ProCooler until about 10 minutes before you plan to evacuate your system... or you will just be wasting desiccant capacity and dramatically reducing the drier ability to absorb moisture like its supposed to.

It should be BIG BOLD on the instructions. DO NOT OPEN OR INSTALL UNTIL READY TO EVACUATE.

$300!!!

Another note I've not seen much is MAKE sure your new expansion valve was set for R134A not R-12.

With R134A you want low side pressures of 18-20psi to get really cold. That control comes from the expansion valve adjustment. If it was set for R-12 you'd see 28-30 low side PSI and get only 40+F or so at the vents w 134a.

So whoever sold you that valve make sure it was set for R134a not R-12. And if they say its the same or doesn't matter you should get it somewhere else.

I think it's best to buy your own 2 stage vacuum pump.
A real good new Robinaire 4 CFM 2 stage pump can be had for around $225 shipped.
I bought this one and it's excellent http://www.thetoolwarehouse.net/shop/ROB-15434.html

You'll need it more than once and you'll know it's in good working shape with clean fresh oil in it if you buy it new.
Nice manifold gauges are usually around $60 on up. Harbor Freight has some for about $40 that should work well.
Always unscrew the yellow hose from the manifold gauge enough to purge the air out of it before filling the system so you're not putting some air back in when charging. It's obvious when the air has been replaced with R134 at the fitting, then tighten it back up and start charging the system with the R134 bottle right side up so gas is going in and not liqued (unless you really know what you're doing) or you may hurt the AC compressor.

And a good vacuum pump is about the same price as paying a shop to do a quickie consumer level 15 minute evacuation and R134 charge here in S. Florida.
You can buy R134 in 30 pound bottles for around $100.
Thats enough refrigerent for about 10 fills depending on the car your doing, so you can do your other cars or friends too.

No shop around here will ever do it right... it takes way too long, oil has to be changed frequently in the vacuum pump (they don't), and they need to do it quick and move on to the next car to make money.

You have to do it yourself to have it done right these days.

JFairman,

I'm with you on almost all of what you said, but if you are talking about the venturi type of pump at Harbor Freight, then I have one almost like it. I bought it from Napa Auto about 6 years ago when there were few options, and before the Chinese decided to make a knock off.

It simply does not pull enough vacuum to be effective in my opinion. I like the one you listed from Tool Warehouse much more. It can pull a vacuum for hourse, which is what I think should be done with a 911 AC system, with all of the hoses and whatnot.

I see the ProCooler is not painted anymore. No matter, it's probably just as good. I wonder how long mine will last.

Those venturi vacuum pumps are not a good way to do it. You would probably burn out a shop compressor running it non stop to use one of them and use a lot of electricity... and they don't pull a vacuum much below 26-27 inches.
They do work good for flushing out brake fluid by sucking it out the brake caliper bleeders. There's no pump oil to get contaminated with brake fluid in the venturi type doing that.

The Robinaire pump I did mention will pull a vacuum to 29" and you can run it all day or night if you want no problem.

I've heard it's best to do it on a hot day... so it might be a good idea to put a fan next to the vacuum pump to help cool the motor on it when running it in the sun on a hot day.

The only thing from Harbor Freight I mentioned were the AC manifold gauges they sell for around $40. I havn't looked at them so I don't know how cheaply made they are, but they would probably be OK for home use.

ok sorry, my mistake.

I bought the ac manifold gauge set from Kragen about 6 years ago when I started to put my system together. They didn't hold up well. I think it's a case of you get what you pay for. The ones from Sears look pretty good, but I'm still amortizing the cost of the Kragen set. I keep everything in plastic storage boxes because it gets dusty around here in the summer time.

MThomas, those are some biiig fans there. Huge condensers too. Can't wait for more pics.

Thanks for the tip on installing the ProCooler last and just before evac. You've now got me rethinking my plans. No luck finding a rental vacuum pump & still concerned that the shop will not evac as long as they should. So, I might just pull the trigger and buy one.

I'll be sure to confirm. Thanks!

Couple of progress pics. Evaporator leak confirmed - check out the oil in the evap box. Good news and bad news on the box removal. Good - found three clips in the bottom of the smugglers box. Bad - found a crack in the lower left hand corner of the box that surely was leaking air and used gorilla glue to patch.

http://forums.pelicanparts.com/uploa...1205065427.jpg

http://forums.pelicanparts.com/uploa...1205065473.jpg

Desert duty unit was a bit of a fitment teaser trying to line up the brackets, spacers and bolts which were too short creating yet another run to Home Depot. Also had to remove the crash bar for easier access.

http://forums.pelicanparts.com/uploa...1205065685.jpg

Test fit pic of one of the rear fender units. These babies are money! Incredibly well designed.

http://forums.pelicanparts.com/uploa...1205065925.jpg

Hi there- It looks like its going to be a COOL summer for you!

Im in ATL also and just started my project - using with the entire Rennaire system and Pro-cooler. I will add the interior Kuehl vent kit .

two questions:
1)I see you are switching to 134, but sticking with the r12 Denso compressor, is that a problem?
2) are you going to add a low pressure cut-off switch (I'm debating if I need one- I'm staying with r12)


also- any luck with a local vacuum pump rental place? I thought about trying those specialty tool rental places instead of just HomeDepot/Autozone.

Thanks

Consider this stuff. Jim Sims recommended it and it seems to work really well.
http://www.refrig.com/nylog.html
Also, on the Procooler, they will replace it after you open it up a few times. I'm not sure if they make you send in your old one but the price was somewhere around $100 to 150, which isn't cheap but beats 299 for a new one. The support on the Procooler is unbeatable!

Never mind, Caught the bottle in your picture:
http://forums.pelicanparts.com/uploa...1204953592.jpg

I noticed this stuff seems to be popular- do you know if the blue or red Nylog is for R12?

On the rear fender condensors, will you still be able to get at the rubber bellows on the bumpers easy? Or will it be harder to take off the bumper now?

I believe the two types of nylog depends on what pressure you are running not the type of refrigerant. I went with the blue based on operating pressure.

Some more pics from todays adventures.

Griffiths Kuehl kit comes with a evap baffle to direct all air flow through the coil.

http://forums.pelicanparts.com/uploa...1205102323.jpg

http://forums.pelicanparts.com/uploa...1205102465.jpg

To wrap the box I used one layer of 1/8" closed cell dynamat foam followed by a layer of 1/8" foam with foil from home depot and a roll of aluminium foil duct tape. This added a full 1/4" and made for a snug fit going back in the smugglers box.....any larger and it would not have gone back in.

http://forums.pelicanparts.com/uploa...1205102516.jpg

http://forums.pelicanparts.com/uploa...1205102567.jpg

http://forums.pelicanparts.com/uploa...1205102784.jpg

Here is the condenser unit mounted in front of the rear tire. I had to move the upper mounting bar that bolts to the Seat belt retractor mounting point to raise the entire unit up so it did not rest on the torsion bar cover. Oh, and here's the best part. After removing the seat belt retracter, we could not get it to extend...tried to unlock the mechanism with no luck....in a last ditch effort we ( we = Paul "carnutzzz") popped the cover off and the spring came flying out....fortunately no one got hurt!

http://forums.pelicanparts.com/uploa...1205102880.jpg

Great stuff Mark, subcribing for next year!!

Is there a crack in the fender, above the condensor, in the last photo?

No, just a shadow line.

You will be freezing this summer, and enjoying every moment. It is great to have good A/C in a 911. Enjoy!

Subscribed. I'm doing a Rennaire kit this spring.

I bought all of the components of the Rennaire system individually, as I did not originally plan on doing the whole kit.

Does anyone know if there is a difference in the evaporator orifice for R134 Vs. R12? I don't remember being given a choice when ordering from our sponsor, but could have been an oversight on my part. I'd rather find out now before I install it and use it.

I plan on using R12, so it could be a problem if it was designed for R134.
Thanks

subscribed

Yes, there is. Check to see if its marked on the expansion valve.

I knew I was going to get blamed for the seat belt mechanism "incident".

Hey- when it comes to labor ya get what you pay for!

No worries - apparently all "we" had to do was re-install and it will function in the proper orientation......so they say. dcautomotive is shipping one today for $75. I've also ordered a new Robinair vacuum pump and gauge set to complete the project 100% DIY. Equipment rental charge when we do your system will be, uh $75!:D

Deal.

Followed your advice and ordered this pump and a guage set from thetoolwarehouse.net. Order placed this AM, shipped this afternoon and will be delivered tomorrow & free shipping to boot! Thanks for the recommendation.

The compressor can be used with R-12 or 134a as long as the correct oil is used. I will be adding a hi/low cutoff switch. It came with my new barrier hose set from Griffiths. Finally, no luck with renting a vacuum pump so I orderd one today.

Thanks Mark- if you are interested in renting it out for a day or two when you are finished it may help recoup the cost- I don't know what part of town you're in but I would be happy to help subsidize the cost. I have a set of Snap-on A/c manifold gauges if you need them.

My system is going to be the complete Rennaire kit with Desert Duty condenser, except that I ordered the "Jim Sims pro-cooler" to try instead of the pricier option from Rennaire. I'm hoping to get a good leak free system (and using the Nylog goo) and will try and stick with R12.

I removed the front factory condenser this weekend- do you think all of the DD condensers are shipped with bolts too short, or will I need longer ones also?

Thanks

Rick

what the best book on car AC that best applies to going from R12 to R134 - there are bits and pieces explained in many posts. When I dive into this I want to have a good list and process for evacuating and charging properly. I like the idea of getting a vacuum pump and DIY. I have an 89 coupe and planning to completely redo the ac system this summer. So I need to decide on model of new compressor, hose kit or DIY hoses, 3 way valve, ProCooler or no ProCooler/etc. Right now I'm leaning toward keeping the same evaporator and condensor assuming there are no leaks.

If you're doing this as a first A/C project I recommend this book.

http://www.acsource.com/index.asp?PageAction=VIEWPROD&ProdID=8

From Mastercool. Covers all you need to know about R-12 v R134a. High low pressure targets. (They are different). Components, troubleshooting, how, when, where. to add oil. and so on...high/low switches. Fan controls...

Rick, happy to work out a deal with you on borrowing the vacuum pump. I'm in Roswell. The issue with the bolts is this. There are two bolts on the passenger side and one bolt on the driver side. Due to the thickness of the DD, the cage drops down leaving a gap between its mounting tabs and the tub. The kit supplies washer spacers but they are not thick enough. I used addl washers to close the gap. I was only able to use one of the supplied bolts on the pass side as the other was obstructed by the crash bar....so I only used one bolt on that side. The drivers side is where the supplied longer bolt is too short....you will need to pick one up at the hardware store that is 1/2" longer. IIRC is is an M6 bolt and you will need one that is about 1- 1/2" long.